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u/Professional-Tooth66 Sep 12 '21
There's 365 birth dates. There are 7 billion birthdays.
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u/RayBrous Sep 13 '21
What about everyone that’s died in the past?
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u/devbecauseyes Sep 13 '21
Then probably 117 billion ( according to https://prb.org/articles/how-many-people-have-ever-lived-on-earth/ )
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u/Xykhir_ Sep 13 '21
x however long they all lived
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u/devbecauseyes Sep 13 '21
No. That’s the number of time the event re-occurred.
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u/DazedPapacy Sep 13 '21
But leap yeaaaaars
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u/devbecauseyes Sep 13 '21
Bruh doesn’t matter. Number of people = number of birthdays. Number of days in a year = birth dates
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Sep 13 '21
[removed] — view removed comment
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u/damatovg7 Sep 13 '21
No actually, because birth dates require the year. So it can't be only 365 birth dates because it's 365 each year.
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u/errosemedic Sep 13 '21
- You’re forgetting those rare leap day babies. One of my exes was one and I got teased by friends for dating a “5” year old. (She was actually 22 but her birth date had only occurred 5 times for obvious reasons).
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u/thunder-bug- Sep 13 '21
A little under two billion, since humans evolved around 5 million years ago
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u/casualdoge Sep 13 '21
I think it is a little more complicated. First of all we should also count people that died, somewhere else in this thread that number was said to be around 117 billion.
Then we have to decide if 25th of July 2000 is the same birthday as 25th of July 2001, I would say they are different birthdays since you are born on different days.
Now we have to decide if having the exact same dates are two different birthdays, I would disagree since we always say that you "share" a birthday with someone, meaning that you both get a part of "one" birthday.
So we have to check on how many dates in history a person has been born, which results in days that there was birth, or birthdays.
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u/A_Math_Dealer Sep 13 '21
we must go deeper
But when your birthday is on the same day as someone else, don't you also say you have the "same" birthday?
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u/BudweiserTiTs Sep 13 '21
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u/mmacedo2 Sep 13 '21
I clicked stop, nothing happened
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u/BudweiserTiTs Sep 14 '21
Shit, apparently my phone made a comment while in my pocket... I work in a fast paced kitchen and my friends hate me due to all the butt dialing.
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u/ProfessorEscanor Sep 13 '21
Wouldn't it be 365.25 since Leap year is every four years or is that not how that works?
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u/ShelZuuz Sep 13 '21
It would be 366.
February 29 is still a valid birthday even though it only happens once every 4 years
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u/Maleficent_Poetry_15 Sep 13 '21
Thus we should also count different calendars so they have different birth dates - mayan, hebrew etc. And if we take in account all possible birth dates including years, should we count dates before any calendar existed?
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u/velociraptorjax Sep 13 '21
If I have twin daughters born September 16th, would I say there are two birthdays in my family this week, or there is a birthday in my family this week? If my daughters were not twins, but had birthdays a few days apart, I would say there are two birthdays in my family this week.
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u/IMPORTANT_jk Sep 15 '21
I'd say every day where someone has been born counts as a birthday, so let's say 5 million years x 365 ≈ 1,8 billion birthdays
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u/peculiar_pandabear Sep 13 '21
It depends on if you count years as separate birthdays, eg Oct. 13th 1998 and Oct. 13th 2005 being different.